Electrodeposited metal



May 18 1926.

C. P. MADSEN' ELECTRODEPOSITED METAL Original Filed April 1919 Eluuewfoz M Momm was May 18, 1926.

' UNITED STATES A --1,5s4 ,95a ATENT OFFICE. 4

CHARLES IP. MADSEN, OF NEWARK, NEW JERSEY, ASSIGNOB TO HADSE'NELL COR- 7 romrion, or new 2031:, n. 1.,

A conrona'rrou o'r NEW YORK.

nnncrnonnrosrrnn METAL.

Application filed April 26, 1919, Serial No. 292,794. Renewed July 28, 1925.

The present invention relates to electro-' deposited metals, particularly what, I term the nickel metals, such as mckel, or-cobalt, or metal alloys containing substantial percentages of either nickel or of cobalt, or both nickel and cobalt. It is the object of the present invention to provide suc nickel metals in a condition in which the same will possess new and extremely valuable 10 properties enabling such nickel metals to beput to a wide variety of important uses I for which nickel, or cobalt 01' alloys ofeither or both of-these metals, as prepared by the customary metallurgical or electrodeposition 6 methods, have hitherto been unavailable.

The present application is a continuation in'part of m copending applications Ser. No. 254,793, lled September 19, 1918, and Ser No. 317,656, filed August 15, 1919.

By way of example, I shall describe herein in detail an illustrative embodiment of my invention particularly as applied to produce electrodeposited nickel in a dense,

reguline condition, which metal is substantially free from pits, pores and hydrogen,

and is at-the same time malleable and ductile to a remarkable degree- For example, the nickel roduct comprising said illustrative embodiment is more workable than hard-rolled copper, even more workable than brass, and almostas workable as soft-rolled copper.

that cobalt or'alloys containing substantial 354 ercentages' of either nickel or cobalt or of 0th these metals, may be produced by means analagous to those herein described for the production of my new kind of nickel and possessing the advantageous properties referred to in connection with said new kind of nickel.

In producing the foregoing new Znickel,

It should however be clearly understood ture.

a smooth, separable deposit o f the electrodeposlted nickel. However, if so desired,

the metal may -be electrodeposited adherentlv, as in the form.of a plating,.which Wlll. adhere closely to the cathode if the latter 1s not given any special treatmentto render the deposit readily. removable and non-adherent. r During deposition the cathode on which the nickel is being electrodeposited, is intermittentl or periodically exposed to a gaseous me um, such as the air, as by removal from the bath or otherwise." The time durmg which the cathode and the electrodeposited nickel carried by it are kept out of the bath should be more than what I term thefmmimum or hydrogen dissipation erlod, which is necessary to permit the ydrogen deposited with the metal to be d1ss1pated or removed by contact with the surrounding gaseous medium,-such as the am This minimum or hydrogen dissipation-period -may be readily determified by trial and experiment and is generally greater than about one second, usually two seconds.

The time durin which the cathode and the deposit carrie by it are .kept out of the bath should not, however, exceed what I term the maximum or critical or separable deposit period, which, in the case here given, is from about 6 to about 16 seconds, by which I mean that if the time during which the cathode and its deposit are kept out of the bath exceeds the said maximum or critical or separable deposit period, on restoring the cathode and its deposit to will not be adherent but will separate or be easily separable from the previous deposit. This results in a laminated, weak metal, a condition which is obviously to be avoided, where a sound unitary metal is desired.

The frequency of removal or exposure frequency period is determined by the factors of deposition which influence hydrogen liberation, such as the de cc of exactness of neutrality, current density, and tempera- I have found that in the bath here described by way of example, and operatin at a temperature of about 130 F., and wit a current density of about 10 amperes per square decimeter, this period may be from 1 to 2 minutes.

In order, moreover, that the electrodeposited metal, such as the nickel in the example the bath, the succeeding deposit iron, may not only be dense, reguline and ice from pores and hydrogen, but in order also that said metal shall be free from what are known as pits in the art of the deposition of the nickel metals, I add to the bath, preferably before starting the electrodeposition, a quantity of finely "divided n ckel hydrate, preferably freshly precipitated nickel hydrate (NiO HQ and probably existing in a colloidal cond1t1 on, wh ch nickel hydrate remains in suspens1on 1n the bath durin electrodeposition. While the quantity of hydrate so added may vary within considerable limits, I prefer to add from 1 to 5 grams, generally 1 gram, of said colloidal nickel hydrate to each liter of bath solution.

I have discovered that by adding to the bath certain salts, such as the sulphates, of the alkali metals, preferably sodium, finely divided or colloidal nickel hydrate is produced and held in suspension in the bath. This freshly and continuouslyproduced hydrate replenishes the hydrate which during the operation of the bath aggregates or for other reasons goes out of suspension and drops to thebottom of the bath. Such salts have further beneficial efiects and greatly improve the'operation of the bath and the character of the deposits formed. For this purpose I may add varying amounts, such as from about 1 to about 10 grams, preferably 1 gram, of sodium sulphate for each liter of bath solution.

The action of the colloid-producing substance, such as the sodium sulphate, described above, is to produce by and during electrode osition, some caustic soda or sodium hy roxide. The caustic soda orsodium hydroxide thus produced, by interaction with the nickel salts present in the bath, such as the nickel sulphate, generates finely divided or coll idal nickel h drate which remains suspended in the bat The interaction at the same time re-generates the sodium sulphate. The sodium sulphate or its equivalent also acts to assist the deposition and to improve the character of the deposit, which factors are also further assisted by the initial addition of nickel hydrate in finely divided or colloidal condition to the bath.

In the accom anying drawing, I have diagrammatically lllustrated a form of apparatus in which the foregoing illustrative embodiment of my invention may be carried out.

Referring to these drawings:

Figure 1 is a -cross section; and

Figure 2 is a longitudinal section of such apparatus.

The apparatus comprises briefly, a vat 1, for containing the bath 2. 3 is the anode and 4 the connector for supplying said anode with current. The cathode 15 indicated at 5 and its conductor at 6. At 7 is indicated eneral any suitable means, which may, if

esired be manual] operated, for intermittently or periodica 1y removing the cathode from the bath, as set forth above.

The resulting roduct, as in the case of nickel in the il ustrative embodiment set forth above, is, as before stated, dense reguline, homogeneous, malleable and ductile. The new nickel herein described is substantially free from pores and pits and contains no appreciable amount of hydro en.

It is of course, to be understoo that where a deposit of cobalt, havin the foregoing desirable properties, is desired to be produced, a cobalt anode is used in place of the nickel anode, and cobalt compounds are used in place of the correspondin nickel com pounds. Where alloys of eit or nickel or of cobalt or of both of these metals are desired to be produced, means analogous to the means herein set forth for the deposition of nickel and of cobalt in the desired condition and having the desired properties may be employed.

The nickel herein described differs in character from the nickel obtained by the usual metallurgical processes in that my new.

nickel is free from the usual poisonous contents such as sulphur, silicon, arsenic, carbon carbides, oxygen, and other gases and oxide containing com ounds, generally present in metallurgical nlckel and rendering the same imperfect and more difficult to work.

Furthermore, my new nickel is to be further differentiated from the ordinary metallurgical nickel in that it has a finer and more even rain than such metallurgical nickel, as is s own by metallographic micro-photographs. It is also considerably purer than such metallurgical nickel, resists chemical action better and has a higher melting point.

'l'he nickel described herein is also to be differentiated from the usual electrodeposited nickel in that it is substantially free from pores, pits and hydro en, and is malleable and ductile to a very hi h degree, unlike the usual electrodeposited mckei which is porous, contains a large hydrogen content and is brittle and unworkable.

A further difi'erence in character between my new nickel and the ordinary metallur cal nickel is shown by the fact that the fi m of oxide formed by heatin my new nickel in an oxidizing atmosphere is thinner, finer in texture and more adherent and flexible than the oxide coating formed by similar treatment of ordinary metallur ical nickel. Furthermore, such oxide coating in the case of my new nickel is of a different color, generally yellow to brown, while the oxide coating on the metallurgical nickel is generally violet or indigo in color.

It is of course, to be understood that the invention is not to be limited to the specific illustrative embodiment herein described for meeeee y 8 purposes of example on] It is also to he mid substantially free from pores, pits and understood that the epplieent does not wish hydrogen. v

to have the invention 01 the eppended claims 2. As en article of manufacture, substam in any way limited by and particular theory tielly pure eleetrodeposited nickel of a dense, 15

e of operation which he may now hold and reguline structure, hein malleable and duowhich may be suggested by the foregoing tile, and substantially ree from pores, pits detailed description. and hydrogen.

What I claim "is: In testimony whereof, I have signed my 1. As an article of manufacture, eleetroneme to this specification this 26th day of m 1 deposited nickel metal of a dense, r- April 1919 line structure, being -malleable and ductile, CHARLES P. MADSEN. 

